Parents returning to work after childbirth is an important question for understanding the trajectory of people's lives and professional careers amid current debates about gender equality and work-life balance (WLB); being WLB understood as satisfaction and good functioning at work and at home with minimal conflict between parents' roles at both domains (Clark, 2000).

In the case of women, the benefits of they being employed are broad, including improvements in their mental and physical health, social support, and financial resources (Coulson et al., 2012), and many countries have become aware of the need to create conditions that facilitate women's abilities to combine their working and family lives (Kreyenfeld, 2010). At the organization level, WLB is also appreciated because work-family conflict will lead women to a re-evaluation of priorities, decreased organizational commitment (Fitzenberger et al., 2016), and harmed job-related well-being (henceforth, job well-being). Job well-being can be seen as an indicator of quality of working lives, e.g., occupational health (Schulte and Vainio, 2010), and a relevant determinant of performance at the individual or organizational levels, e.g., productivity and absenteeism (Boyd, 1997). Well-being in the workplace is defined as satisfaction with work and non-work domains, as well as general health (Aazami et al., 2015). Therefore, well-being is relevant for both employees and their organizations.

Nowadays, more than men, women quite often face demanding conditions to return to work after childbirth because of the specific maternal and infant factors involved (e.g., childcare, high women responsibilities with childcare, change of women's habits, daily physical and emotional effort to conciliate duties at home and work). Therefore, general conditions offered by governments aimed at reconciling working and family responsibilities may be insufficient and some firms may have an incentive to complement them applying suitable policies and practices, but this is not always usual. Therefore, there exists a relevant social concern about the issue, resulting in a rise in interest in maternal employment among academics (Skouteris et al., 2007), as well as journalists, editors, and other contributors covering highlights, articles, and tribune sections on this topic.

For example, Ms. Carme Chacón made it to the front pages and headlines of many international newspapers in 2008 when she became Spain's first female Defense Minister. Doubts emerged regarding her capacity to carry out her responsibilities as a minister while providing the attention a newborn requires and helping to raise her child. However, we can now say that Ms Chacón, who died from a congenital heart condition in 2017 at the early age of 46, may be remembered as a symbol of the reconciliation of family and work duties. Indeed, she accepted the charge to the Defense ministry in part because this governmental department had its own kindergarten¹. Additionally, she was highly supported by the President of the government, and her defense duties were temporarily taken over by the Interior Minister after childbirth. However, although Spanish law allows for 16 weeks of maternity leave (paid time off), she was back at work within 6 weeks.

Obviously, the circumstances of this case would not have been news if the person affected by the official appointment and the forthcoming newborn was a man, showing once again that WLB is still a problem that profoundly affects women. This case may be unrepresentative of the majority of female employees, but illustrates the cost of motherhood in professional careers with high aspirations, as well as the relevance of superior support and the existence of conditions to facilitate WLB (e.g., the kindergarten) to help women return to work. In this case, they were the crucial factors that allowed Ms. Chacón to bring her child up and retain her post as Minister. In developing this professional role, although she felt some “sensation of guilt that moms have when their work is intense,” she was sufficiently vigorous and in good spirits to work in order to fulfill her dreams and job goals². In other words, she demonstrated job well-being, which, according to Boyd (1997), is quite relevant to making good contributions at work. Although this case illustrates that reconciliation is possible, conditions that allow women to properly balance work and family life duties after childbirth and to enhance their actual performance and perception of well-being at work are not always present in firms. The current study aims to contribute to this area of research.

Although motherhood represents one of the most important stages in women's lives and is quite relevant in societies, women still encounter diverse difficulties after becoming mothers, even during the first 3 years postpartum (Hsu and Wickrama, 2017). While motherhood is often considered a positive and fulfilling experience (Umberson et al., 2010), in some cases, it is more difficult than expected and eventually perceived as a negative experience (Nichols and Roux, 2004) because it involves facing new situations that are potentially stressful, e.g., childcare, change of habits, and personal time (Fisher and Stocky, 2003). All of a sudden, working mothers have to simultaneously manage a job, raise children, and maintain a home involving a challenging physical and emotional effort (Maynard and Blain, 2005). Moreover, mothers commonly experience fatigue, sleep-related problems, and in some cases, high levels of stress and depression (Maynard and Blain, 2005). Consequently, women can become highly vulnerable in face of the potential conflict between the roles of mother and employee.

Hence, the return to work after childbirth does not always involve an adequate performance level of new mothers, particularly when there is lack of engagement from the employers regarding WLB (Guendelman et al., 2014). Therefore, managing the return to work of women after childbirth is a challenge for the human resources departments of companies (Kossek et al., 2010). For example, flexible work arrangements are considered suitable practices (Lee et al., 2002).

Previous research has investigated women's experiences balancing work and family life after childbirth from different perspectives (Grice et al., 2008, 2011, 2017). For example, some studies have shown that work conditions related to WLB that are established by firms can affect maternal postpartum mental health (Cooklin et al., 2011; Coulson et al., 2012) and well-being (Cooklin et al., 2011). However, managers' opinions on the practices being implemented can be quite different from the employees' views about such practices (e.g., Khilji and Wang, 2006), and as a consequence Farndale and Paauwe (2007) recommended the study of conditions implemented by firms from the perception of employees. However, the link between women's perceptions of WLB practices offered by their firms and job well-being following childbirth has been under-examined. To better understand how women address their return to work, we try to fill this gap in the literature by analyzing the impact of women's perceived WLB in their firms on job well-being after childbirth.

In addition, since women's use of WLB alternatives such as flexible arrangement formally offered by the firm might also work against them because being considered as showing lack of organizational commitment (Woolnough and Redshaw, 2016), research on this topic could benefit from considering postulates of the theory of perceived organizational support (Eisenberger et al., 1986). This theory posits that employees develop beliefs regarding the extent to which the company cares about their well-being and values their actual contributions (e.g., not being evaluated solely based on their use of a flexible arrangement). The SS is clearly a good indicator of company support (Boselie et al., 2005). We took into account this theory and studied the SS, as well as its potential moderating role in the effect of WLB on women's job well-beings. Certainly, it can be expected that supervisors' opinions, whether positive or negative, about women's use of existing WLB alternatives may be relevant for women, as these opinions may condition the colleagues' views and the social support women experience after returning to work.

The present study addresses the scarcity of research on the impact of employed postpartum women's perceptions of WLB on their job well-being. In particular, previous and scarce research has analyzed the impact of WLB and SS separately on women's general mental health after childbirth (Grice et al., 2008) and the impact of perceived work-schedule flexibility on the general well-being of working parents with children under age 18 (Jang, 2009). In this research, well-being was essentially measured by stress-related symptoms. Therefore, to the best of our knowledge, we are the first to analyze the impact of the perception of WLB, SS, and their interaction, on women's perceptions of job well-being in the particular setting of having with children under the age of one's perceptions of job well-being. Moreover, we extended this analysis to men after childbirth. On this basis, the current study aimed to analyze the following: (a) the influence of the perceived WLB and SS on women work-related outcomes such as job well-being after childbirth, and (b) the moderating effect of SS on the effect of WLB on women's job well-beings, in both cases comparing women with men to find qualified results. We analyzed two sub-samples of 664 working women and 749 working men with children under the age of one in 27 European countries. The use of these two sub-samples was highly appropriate because it allowed the study of the specific conditions that affect the relationships between the studied variables for women in comparison to men, thus assuring that results did not only reflect what any employee needs at work but also illustrate the specific requirements of the collective under study.

Tables 1, 2 present the means, standard deviations, and correlations for the study variables for both sub-samples of employed mothers and employed fathers. General health, WLB, and SS were positively associated with job well-being for both employed women and men, whereas the interaction variable (work-life-balance × SS) had a negative and weak correlation with well-being for both sub-samples. Concerning multicollinearity in the data, the general rule of thumb is that correlation should not exceed 0.75 between independent variables (Tsui et al., 1995). Therefore, excluding correlations involving job well-being, the highest correlations were between general health and WLB, at 0.142 in the female sub-sample and 0.214 in the male sub-sample. These correlations suggest that multicollinearity was not a problem. In addition, our tests for hierarchical regressions (Table 3) showed that the variance inflation factor (VIF) values ranged from 1.006 to 1.076 in the female sub-sample and from 1.011 to 1.093 in the male sub-sample, both of which were much lower than the recommended cut-off threshold of 10 (Hair et al., 1992). The highest condition number for all the regressions in the female sub-sample was 18.174 lower than the recommended cut-off of 20 (Belsley, 1991) and reached 21.288 in the male sub-sample, slightly higher than this limit. These statistics suggest that multicollinearity was not a problem in the data.

Table 3 shows the regressions estimated to analyze the direct and moderating effects proposed in the hypotheses. The two control variables had different effects in the equations estimated. First, since women may be vulnerable in terms of general health given their postpartum situation, their health was important for their job well-being (β = 0.359^***). Even by 6 months postpartum, some women did not feel completely recovered from childbirth. Although general health was also relevant for men and positively conditioned their job well-being (β = 0.174^**), for women, this relationship was doubly important. Moreover, the number of children, in addition to the newborn, was also relevant to the job well-being of women, and the higher the number of children is, the greater the perceived job well-being (β = 0.135^*), but this variable did not affect men's job well-beings. This difference probably arose because experienced mothers have learned to organize the multiple tasks they must undertake in order to perform well at work and at home. This finding illustrates another reason to demand more resources that help to address the difficult postpartum situation.

Furthermore, our results offer additional evidence that employed women after childbirth had a higher need for organizational support through WLB practices and SS in order to increase their job well-being. Regarding the direct effects, the results confirmed hypotheses H1 and H2 and verified the relevance of WLB and SS on women's well-beings. Specifically, we identified significant positive expected effects (β = 0.155^** and 0.168^**). Nevertheless, the effect of WLB on job well-being was non-significant in the male sub-sample probably because women are more involved in and committed to home life than men, and women need their firms to provide them with working hours that fit with their family requirements. This result suggests that it might be interesting to develop WLB practices based on gender.

Moreover, we found a significant and negative impact for the interaction effect of WLB and SS on job well-being (step 3 in Table 3), but this interaction effect exists only in the case of women (Figure 1) and was non-significant for the male sub-sample. This effect is the opposite of what we expected; thus, H3 was not supported. The negative interaction indicates that the joint effect of WLB practices and supervisor support is different before and after the cutoff point depicted in Figure 1.

The negative effect indicates that, before the cutoff point, supervisor support is highly relevant to increasing women's well-beings, although the firm provides opportunities to balance work and life. However, after the cut-off point, that is, in the presence of highly relevant WLB practices, the role of supervisor support is less important to increasing well-being.

This study addressed two research objectives.

The first objective was to measure the direct impact of WLB and SS on the well-being of mothers and fathers with children under the age of one. Additionally, we studied the potential moderating role of SS on the effect that WLB exerts on job well-being for mothers and fathers. Consistent with previous studies on employees' well-beings, we found that WLB and SS positively influenced the well-beings of female employees after childbirth (e.g., Grice et al., 2008; Jang, 2009; Cooklin et al., 2011), but the effect of WLB on job well-being was non-significant for the men. These results offer evidence of the higher need among employees who are mothers for WLB practices in order to increase their job well-being when returning to work after childbirth. Accordingly, a practical implication of this study refers to the location of WLB and flexibility debates. Our results suggest that many times, such debate occurs within a gender-neutral context and should instead provide encouragement for gendered WLB practices, which are particularly suitable for a specific life stage such as returning to work after motherhood. Regarding SS, as both women and men need such work-related support, after the arrival of a new son or daughter, in order to facilitate returning to work, our study showed the relevant role that the supervisor has, rather than the firm's formalized organizational practices. Certainly, this finding stresses the relevance of the human factor over human resource practices in addressing the difficulties that parents returning to work face when they have children under the age of one. This conclusion emerges if SS and WLB practices are analyzed separately.

Regarding the SS moderating effect, SS was not found to affect the relationship between WLB practices and job well-being for men, but it moderated this relationship for women. The identified interaction was significant and negative, which is the opposite of what we expected on the base of literature that focus on the moderation effect of supervisor support and WLB on employees outcomes (Allen et al., 2000; Wang et al., 2014; Baeriswyl et al., 2016). Obviously, when a significant interaction is detected, its interpretation becomes critically important. In our case, the estimated interaction indicated that to enhance women's job well-beings after childbirth, the effect of SS differed depending on whether WLB practices were low or high. It is noteworthy that the joint effect of WLB practices and supervisor support is different before and after the cutoff point in Figure 1, which is in concordance with the negative terms of the interaction that we have found (Table 3).

Before the cut-off point, when women perceived low WLB practices, SS took on a greater role in increasing women's job well-beings. Therefore, the low use of WLB practices was somehow compensated by a supervisor who was supportive and receptive to female employees' family needs, which had a stronger effect on final well-being. In contrast, in cases of a high presence of WLB practices, the relevance of SS, although reinforcing and helping women access to these practices, were less relevant for the improvement of women's well-beings. Focusing on the case of low supervisor support, employee well-being benefits from higher levels of WLB practices. However, if a high level of supervisor support exists, increasing WLB practices has little effect on improving employee well-being.

After the cut-off point, higher levels of well-being can be reached in cases where the organization provides significant WLB practices, even with low existing supervisor support. In other words, supervisor support drops in relevance if the HRP is significant. Additionally, job well-being should reach higher values for women in cases of high WLB practices and some SS, suggesting that women felt more supported and confident in balancing job and family needs when that support is guaranteed by the firm's formalized WLB practices. It happens only after the cut-off point, because before it, the supervisor support is what mainly increases women's well-beings.

Some arguments may justify these results. First, if supervisor support is low, any increase in the number of WLB practices will improve well-being. However, even if supervisor support is high, the organization must place high importance on the application of these practices to improve women's well-beings because the supervisor can offer support to the woman only up to a point, from which greater flexibility should be allowed and even offered by the organization through formalized practices. From another point of view, when there is a certain lack of WLB practices, the supervisor becomes the main support for employed mothers with children under the age of one, as supervisors are close to these employees, interact with them and know first-hand the problems they face daily (e.g., days when children fall ill or do not sleep well). As such, these supervisors become the more relevant organizational medium to help employed mothers balance work and family life. The supervisor is then the only person that can actually offer alternatives to reach such balance and provide the help that really fits women's needs after childbirth. However, this happens till a given point, from which the supervisor has unlikely the authority to offer more support and flexibility to women.

On the basis of the identified SS moderating effect, the present study suggests that despite the increasingly normalized career orientation of females and the higher commitments of firms to ensure WLB, female employees require targeted and adapted WLB policies to return to work after childbirth, and this is likely to be possible only if SS exists, as the supervisor plays a relevant role in facilitating the returning to work in cases where the firm has not a high commitment to the offering of WLB practices. In addition, as the mere offer of some WLB alternatives by the firm may be insufficient for women who access such options because they face prejudices for being considered lacking in commitment to the firm and, consequently, harming their professional career, the support of their immediate supervisor becomes very relevant. The relevance of SS only declines in cases where the firm is firmly committed to the WLB policies.

New practical implications of this study emerged from the SS moderating effect. First, human resource managers and practitioners in firms in which women of childbearing age work should send clear signs to employees through different but simultaneously congruent human resource policies and practices that help them to face the uncertainty associated with their return to work after childbirth. For example, if flexible work arrangements are offered, female employees should not be viewed negatively if they benefit from them, and they should be clearly informed about existing alternatives and supported by supervisors to access to options to facilitate reconciliation and successfully perform their functions at work. Second, supervisors should be advised about their relevant role in the experience of returning to work for both female and male employees. Indeed, this role of supervisors is the only mechanism that our study determined to be relevant for increasing job well-being among men with children under the age of one. For women, supervisors must also take into consideration that they can complement and substitute the WLB alternatives offered by the firm to guarantee women's possibilities of balancing work and life.

The limitations of this study may give rise to further research. First, we studied a small number of practices to analyze WLB, and other ways to reconcile work and family life may have a higher impact on women's job-well-beings compared to flexible work arrangements. Future research could explore whether other human resource practices influence well-being and whether this influence is conditioned by SS. Second, although the data used in this research were compiled from 27 different countries, all countries were European. The Arabic world and Asian cultures, among other countries with idiosyncratic social values that are likely to differ from those of Western countries, were not considered in this study. Therefore, the results should not be generalized without first determining whether the cultural context helps explain women's job well-beings after childbirth. In addition, it could be interesting to replicate this study in other cultures.

AL-C conceived and designed the research questions or hypotheses, performed the literature research on well-being and analyzed the data. AG-C performed the literature research on on female worker after a childbirth, analyzed the data and wrote discussion. LP-A performed the literature research on Work-life balance and women's perceived job well-being after childbirth. DC-M performed the literature research on on Supervisory support and women's perceived job well-being after childbirth.